DRUG-DELIVERY STUDIES IN CACO-2 MONOLAYERS .5. ETHYL GLUCOSIDE ESTERSAS A NOVEL TYPE OF ABSORPTION ENHANCERS

In this study, the absorption enhancing ability of a group of a unique series of fatty acid derivative, ethyl glucoside esters, was evaluate d. Esters of saturated C10-C18 fatty acids as well as an ester derivat ive of the unsaturated oleic acid were include in the study. Caco-2 mo nolayers were used as a model for the human intestinal epithelium. The effect of the ethyl glucoside esters on the intracellular dehydrogena se activity was determined using a staining method based on thiazolyl blue reduction, and cytoplasmic staining with trypan blue was used to characterize the degree of membrane perturbation caused by ethyl gluco side esters. It was found that ethyl glucoside esters of C10 and C12 f atty acids as well as the ester of oleic acid enhanced the penetration of a hydrophilic pore marker (PEG 4000) across the Caco-2 monolayers. The apparent permeability coefficient increased even at concentration of ethyl glucoside esters which only showed minor toxic effects on th e Caco-2 monolayers.